Temperature sensors are used in various systems to measure a temperature of the system or parts thereof, for example to detect overtemperatures. One application of such temperature sensors is in so-called smart systems, which incorporate functions of sensing, actuation and control in order to describe and analyze a situation, and make decisions based on the available data in a predictive or adaptive manner. Conventionally, temperature sensors used in such applications include sigma-delta analog to digital converters (ADC) to convert the sensed temperature into digital data and to achieve a high resolution. In some applications, due to a requirement of a high frequency burst clock (for example 150 MHz clock and 82 μs burst) clocking the ADC, conventional sigma-delta ADCs are sometimes not quite suitable as they consume too much power when clocked in this way.
Some temperature sensors conventionally used are based on the temperature-dependent behavior of semiconductor devices, in particular PN diodes or bipolar transistors coupled as diodes. This temperature-dependent behavior is at least in part due to the fact that the bandgap of semiconductors varies with temperature, in particular decreases with temperature. Conventional solutions may have drawbacks like comparatively small temperature range, high power consumption or comparatively large chip area requirements.